Can you give us some examples? Please provide a public link (no password) that we can check out. '''No Personal Information Please ! ''' Make sure you are not blocking content. https://support.mozilla.org/en-US/kb/enhanced-tracking-protection-firefox-desktop also see https://blog.mozilla.org/security/2021/03/23/introducing-smartblock/ https://support.mozilla.org/en-US/kb/smartblock-enhanced-tracking-protection --------------- [https://support.mozilla.org/en-US/kb/diagnose-firefox-issues-using-troubleshoot-mode Diagnose Firefox issues using Troubleshoot(Safe) Mode] {web link} A small dialog should appear. Click '''Start In Troubleshoot(Safe) Mode''' (not Refresh). Is the problem still there? Many site issues can be caused by corrupt cookies or cache. '''Warning ! ! ''' This will log you out of sites you're logged in to. You may also lose any settings for that website. * [https://support.mozilla.org/en-US/kb/delete-cookies-remove-info-websites-stored Delete cookies to remove the information websites have stored on your computer] {web link} * [https://support.mozilla.org/en-US/kb/how-clear-firefox-cache How to clear the Firefox cache] {web link}

Note that it is possible that other browser load the video from the cache. There is a change in Firefox 96 related to cookies and insecure sites. *https://developer.mozilla.org/en-US/docs/Mozilla/Firefox/Releases/96#http See also: *[/questions/1363998] blocked 3rd party cookies As a workaround for now you can modify this pref on the about:config page to revert this change. *about:config => network.cookie.sameSite.laxByDefault = false You can open the <b>about:config</b> page via the location/address bar. You can accept the warning and click "I accept the risk!" to continue. *https://support.mozilla.org/en-US/kb/about-config-editor-firefox *https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Set-Cookie/SameSite